[FIXED] django async if else use a thread or sync_to_async

Issue

I don't know where the error is.

I am using Django ORM asynchronously.

@database_sync_to_async
def filter_data(**kwargs):
    return FinishAnimateModel.objects.filter(**kwargs)

async def receive(self, text_data=None, bytes_data=None):
    ...
    if data['msg']:
        print('in')
        model = await DB.Myself.filter_data(name__contains='')
        print('ok')
    else:
        print('else')
        model = await DB.Myself.filter_data(name__contains='')
        print(model, 'model')

In if log

in
ok

In else log

else
You cannot call this from an async context - use a thread or sync_to_async.

I try to reverse if else.

async def receive(self, text_data=None, bytes_data=None):
    ...
    if not data['msg']:
        pass
    else:
        print('else')
        model = await DB.Myself.filter_data(name__contains='')
        print(model, 'model')

In else log

else
You cannot call this from an async context - use a thread or sync_to_async.

Why?

Can you help me?

Solution

It looks like it could be passed in the if part only because you didn't print(model) in there. If you do, then you should see the same problem.

However, I may not be able to answer the question you asked -- It's too little information.

All I can say is that the type returned by filter() is QuerySet, if you want to print it, you must convert it to list type.

Reference: Retrieving specific objects with filters

So, maybe you can modify it like this:

async def receive(self, text_data=None, bytes_data=None):
    ...
    if not data['msg']:
        print('in')
        model = list(await DB.Myself.filter_data(name__contains=''))
        print(model, 'ok')
    else:
        print('else')
        model = list(await DB.Myself.filter_data(name__contains=''))
        print(model, 'model')

Or

@database_sync_to_async
def filter_data(**kwargs):
    return list(FinishAnimateModel.objects.filter(**kwargs))

Answered By - LianSheng